fetchAssetCollectionsWithType 仅检索视频

Question

我正致力于在 iOS 中制作自定义画廊视图为此，我正在使用迄今为止效果很好的照片框架我无法让它工作的一件事是仅将结果获取到 return VIDEOS

我试过了 let result = PHAssetCollection.fetchAssetCollectionsWithType(.Moment, subtype: .SmartAlbumVideos, options: nil) 但它仍在检索图像我想知道语法是否错误

感谢您的帮助

Answer 1

好的，我找到了问题的答案基本上我需要使用一个谓词，这基本上是说检索媒体类型为视频的资产，并按 creationDate

对其进行排序

let allVideosOptions = PHFetchOptions()
allVideosOptions.predicate = NSPredicate(format: "mediaType == %d", PHAssetMediaType.Video.rawValue)
allVideosOptions.sortDescriptors = [NSSortDescriptor(key: "creationDate", ascending: false)]
videos = PHAsset.fetchAssetsWithOptions(allVideosOptions)

Answer 2

这里有 objective-c 个代码。

PHFetchOptions* fetchOptions;

// all photos
fetchOptions = [[PHFetchOptions alloc] init];
fetchOptions.sortDescriptors = @[[NSSortDescriptor sortDescriptorWithKey:@"creationDate" ascending:NO]];
if( self.bOnlyVideo == YES ) {
    fetchOptions.predicate = [NSPredicate predicateWithFormat:@"mediaType == %d", PHAssetMediaTypeVideo];
} else if( self.bOnlyPhoto == YES ) {
    fetchOptions.predicate = [NSPredicate predicateWithFormat:@"mediaType == %d", PHAssetMediaTypeImage];
}
self.allPhotos = [PHAsset fetchAssetsWithOptions:fetchOptions];
[fetchOptions release], fetchOptions = nil;

fetchAssetCollectionsWithType 仅检索视频

fetchAssetCollectionsWithType to only retrieve videos

ios

swift

ios8

photosframework